Vanadium based zinc spinel oxides: Potential materials as photoanode for water oxidation and optoelectronic devices
Vanadium based zinc spinel oxides: Potential materials as photoanode for water oxidation and optoelectronic devices
复制标题
DOI：
10.1016/j.ijhydene.2021.06.073
复制
发表时间：
2021-08
影响因子：
7.2
通讯作者：
Zeeshan Tariq;S. Rehman;Xiaoming Zhang;F. Butt;S. Feng;B. Haq;B. Cheng;Chuanbo Li
中科院分区：
文献类型：
--
作者：
Zeeshan Tariq;S. Rehman;Xiaoming Zhang;F. Butt;S. Feng;B. Haq;B. Cheng;Chuanbo Li
近年来，层状锌基钒尖晶石氧化物（ZnVOs）已经显示出一种有趣的方式来完成能量转换，存储和利用问题的挑战。本文通过第一性原理计算，对AV2M（其中a = Zn, Zn2, Zn3, Zn4, M = O4, O6, O7, O8, o9）的电子、光催化和光学性质进行了全面的研究。带负号的生成能表示纯元素可能生成最终化合物，而带负号的内聚能表示化合物能量稳定。为了更好地逼近电子性质（能带结构和态密度），还考虑了自旋极化计算。所有层状结构在0.3 eV - 2.4 eV范围内均表现出间接带隙，而在2.3 eV - 3.50 eV范围内则表现出混合趋势。合适的带边和足够大的析氧反应动力学过电位（ΔEV≥1.244 eV）使其成为水分解光阳极的潜在候选者。与水的氧化电位相比，znv2o4具有较小的动力学过电位，因此更适合于OER。有趣的是，所有ZnVOs的光吸收系数都非常大（~105cm−1）。层状锌基钒尖晶石氧化物表面的光生电子和空穴使这些尖晶石氧化物成为光催化水分解和太阳能转换的有前途的材料。
In the recent past, layered zinc-based vanadium spinel oxides (ZnVOs) have shown an intriguing way to accomplish the challenges of energy conversion, storage, and utilization issues. Here, through first-principles calculations, a comprehensive study has been carried out to investigate the AV2M (where A = Zn, Zn2, Zn3, Zn4,and M = O4, O6, O7, O8, O9respectively) electronic, photocatalytic, and optical properties. Formation energies with a negative sign express that the final compounds from the pure elements are possible and cohesive energies revealed that compounds are energetically stable. Spin-polarized calculations are also taken into account for better approximation of the electronic properties (band structure and density of states). All layered structures show indirect bandgap for spin-up calculations in range 0.3 eV–2.4 eV, while spin-down calculations show mix trends in range 2.3 eV–3.50 eV. An appropriate band edge with large enough kinetic over-potentials of the oxygen evolution reaction (ΔEV≥ 1.244 eV) makes them potential candidates as photoanode for water splitting. ZnV2O4is more suitable for OER as it has small kinetic overpotential as compared to the oxidation potential of water. Interestingly, all ZnVOs display a dramatically large coefficient (~105cm−1) for optical absorption. Photogenerated electrons and holes on the layered zinc-based vanadium spinel oxide surfaces could make these spinel oxides promising materials for photocatalytic water splitting and solar energy conversion.